Silver halide color photographic materials, particularly photographic materials for taking pictures, are required to be highly sensitive, produce good image quality, few variations in photographic characteristics during storage and excellent image retaining qualities after processing.
Acylacetanilide-type couplers having active methylene (methine) groups are generally known as yellow couplers for forming images of color photographs However, the images formed by these couplers have low developed color density and dye formation rate. In particular, when these couplers are used as development restrainers, so-called DIR couplers, they must be used in large amounts due to their low activity, which causes compromises in color image fastness and hue; and, increases cost.
On the other hand, for color development, techniques for reducing the amount of waste liquor generated in processing have recently been investigated, and are widely utilized in some processing stages. In been proposed because the environmental impact of waste liquor generated in color development processes is very serious. Examples include reproduction methods with color developers using activated carbon described in JP-B-55-1571 (the term "JP-B" as used herein means an "examined Japanese patent publication") and JP-A-58-14831 the term "JP-A" as used herein means an "unexamined published Japanese patent application"), ion exchange membranes described in JP-A-52-105820 and ion exchange resins described in JP-A-55-144240, JP-A-57-146249 and JP-A-61-95352, as well as methods utilizing electrodialysis described in JP-A-54-37731, JP-A-56-1048, JP-A-56-1049, JP-A-56-27142, JP-A-56-33644, JP-A-56-149036, JP-B-61-10199.
However, in the above-described methods the composition of the developing solutions must be continuously monitored and strictly controlled, which requires high-level control techniques and expensive apparatus. As a result, these methods are actually only used in some large-scale laboratories.
Alternatively, low replenishment processing methods are also used in which the composition of the replenishers of color developers (hereinafter referred to as color development replenishers) are adjusted to reduce the replenishment rate, without using the reproduction methods described above. Examples of the adjustment of the replenisher composition in low replenishment processing include methods for concentrating consumable ingredients such as color developing agents and preservatives so that the ingredients are supplied in required amounts even if the replenishment rate is reduced.
When a photographic material is processed, halogen ions are released in the color developer. In low replenishment processing, the bromine ion concentration in the color developer increases over time, which restrains development. In order to prevent this phenomenon, therefore, methods are also usually employed in which the concentration of bromides contained in replenishers is previously reduced compared to that used in ordinary replenishment processing.
Such low replenishment processing has the advantage that the processing may be conducted without full analysis of the solution composition, in addition to the above-described advantages such as prevention of water pollution and reduction in processing cost.
The replenishment rate of the color developers which have previously been used varies depending on the type of photographic materials used. Taking a picture taking color negative film as an example, the replenishment rate is generally 900 to 1,200 ml/m.sup.2 of photographic material, but when there is requirement for reduced replenishment, the film is processed at a replenishment rate of 600 ml/m.sup.2 of photographic material.
However, attempts to conduct rapid processing under such reduced replenishment revealed that the problem of fluctuations in photographic characteristics became significant. For this reason, the development of techniques having the advantage of simplicity in low replenishment processing as described above and meeting the demand of rapid processing have been desired.